NMI request/release, version 2

diff -ur linux.orig/arch/i386/kernel/i386_ksyms.c linux/arch/i386/kernel/i386_ksyms.c
@@ -90,6 +90,9 @@
 EXPORT_SYMBOL(cpu_khz);
 EXPORT_SYMBOL(apm_info);
 
+EXPORT_SYMBOL(request_nmi);
+EXPORT_SYMBOL(release_nmi);
+
 #ifdef CONFIG_DEBUG_IOVIRT
 EXPORT_SYMBOL(__io_virt_debug);
 #endif

diff -ur linux.orig/arch/i386/kernel/irq.c linux/arch/i386/kernel/irq.c
@@ -131,6 +131,8 @@
  * Generic, controller-independent functions:
  */
 
+extern void nmi_append_user_names(struct seq_file *p);
+
 int show_interrupts(struct seq_file *p, void *v)
 {
 	int i, j;

@@ -166,6 +168,8 @@
 	for (j = 0; j < NR_CPUS; j++)
 		if (cpu_online(j))
 			p += seq_printf(p, "%10u ", nmi_count(j));
+	seq_printf(p, "                ");
+	nmi_append_user_names(p);
 	seq_putc(p, '\n');
 #if CONFIG_X86_LOCAL_APIC
 	seq_printf(p, "LOC: ");

diff -ur linux.orig/arch/i386/kernel/nmi.c linux/arch/i386/kernel/nmi.c
@@ -20,6 +20,7 @@
 #include <linux/interrupt.h>
 #include <linux/mc146818rtc.h>
 #include <linux/kernel_stat.h>
+#include <linux/notifier.h>
 
 #include <asm/smp.h>
 #include <asm/mtrr.h>

@@ -102,6 +103,16 @@
 	return 0;
 }
 
+static int nmi_watchdog_tick (void * dev_id, struct pt_regs * regs);
+
+static struct nmi_handler nmi_watchdog_handler =
+{
+	.dev_name = "nmi_watchdog",
+	.dev_id   = NULL,
+	.handler  = nmi_watchdog_tick,
+	.priority = 255 /* We want to be relatively high priority. */
+};
+
 static int __init setup_nmi_watchdog(char *str)
 {
 	int nmi;

@@ -131,6 +142,9 @@
 	 */
 	if (nmi == NMI_IO_APIC)
 		nmi_watchdog = nmi;
+
+	request_nmi(&nmi_watchdog_handler);
+
 	return 1;
 }
 

@@ -350,7 +364,7 @@
 		alert_counter[i] = 0;
 }
 
-void nmi_watchdog_tick (struct pt_regs * regs)
+static int nmi_watchdog_tick (void * dev_id, struct pt_regs * regs)
 {
 
 	/*

@@ -401,4 +415,6 @@
 		}
 		wrmsr(nmi_perfctr_msr, -(cpu_khz/nmi_hz*1000), -1);
 	}
+
+	return NOTIFY_OK;
 }

164 lines not on this page · raw message

diff -ur linux.orig/include/asm-i386/apic.h linux/include/asm-i386/apic.h
@@ -79,7 +79,6 @@
 extern void setup_boot_APIC_clock (void);
 extern void setup_secondary_APIC_clock (void);
 extern void setup_apic_nmi_watchdog (void);
-extern inline void nmi_watchdog_tick (struct pt_regs * regs);
 extern int APIC_init_uniprocessor (void);
 extern void disable_APIC_timer(void);
 extern void enable_APIC_timer(void);

diff -ur linux.orig/include/asm-i386/irq.h linux/include/asm-i386/irq.h
@@ -28,4 +28,30 @@
 #define ARCH_HAS_NMI_WATCHDOG		/* See include/linux/nmi.h */
 #endif
 
+
+/* Structure for handling NMIs */
+#define HAVE_NMI_HANDLER	1
+struct nmi_handler
+{
+	char *dev_name;
+	void *dev_id;
+	int  (*handler)(void *dev_id, struct pt_regs *regs);
+	int  priority; /* Handlers called in priority order. */
+
+	volatile struct nmi_handler *next;
+};
+
+/**
+ * Register a handler to get called when an NMI occurs.  If the
+ * handler actually handles the NMI, it should return NOTIFY_OK.  If
+ * it did not handle the NMI, it should return NOTIFY_DONE.  It may or
+ * on NOTIFY_STOP_MASK to the return value if it does not want other
+ * handlers after it to be notified.  Note that this is a slow-path
+ * handler, if you have a fast-path handler there's another tie-in
+ * for you.  See the oprofile code.
+ */
+int request_nmi(struct nmi_handler *handler);
+void release_nmi(struct nmi_handler *handler);
+
+
 #endif /* _ASM_IRQ_H */